Allow a 'default locale' and locale switcher on status pages

[wampiedriessen]

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Description

Fixes #2196, fixes #1643, fixes #3487
I use UptimeKuma myself, and found myself in need of a 'default locale' selector for the status page.

Since I thought: we do not want to force a language upon anybody, i also built an optional 'locale selector' in the top-right corner of the statuspage.

If somebody (logged in user) already has a known locale (which is set in the localstore) that language is used.
If the page has a default locale, that language is set temporarily (only for that page)
If the statuspage has a language selector and it is used, that language is saved into the localstore (I presume a user wants the same language on all status-pages of the website)

Type of change

Please delete any options that are not relevant.

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update (maybe, don't really know)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

[wampiedriessen]

re-reading the contributing guide I seem to have overlooked the 'create an empty pull request as to allow for discussion first'.

My apologies, feel free to still discuss these features as if they hadn't been written :)

[wampiedriessen]

Hi @louislam ,

Really sorry to bother you.

I have altered my migration into a knex migration, but it seems that the auto-test does not correctly bootstrap the base migrations for the project.

Am I doing something wrong, or should there be a fix introduced into the auto-tester?

[louislam]

I am re-implementing new auto-test due to this issue. You could ignore them at this moment if you tested successfully in your local environment.

#3893

[louislam]

Tested. It doesn't seem to be working for me.

• No matter on or off, the dropdown is always on.
• The default language is not working, i set it to Japanese, but it is still show my primary language (Traditional Chinese) even in a private tab.

The database looks fine.

[CommanderStorm]

Tested. It doesn't seem to be working for me

@wampiedriessen
Sorry to bother you, but might this be an issue of different testing strategy? How did you test the PR?

[wampiedriessen]

Hey guys,
I'm back from a long holiday.

This PR was waiting for the introduction of v2.
I believe something broke when the new migration system was introduced or something?

I had tested it waay before, using the devcontainer and a browser.

I might find the time somewhere in the future to revisit these changes and fix things